Calendula diffusa Salisb.
Calendula diffusa Salisb. is a flowering plant that belongs to the family Asteraceae. It is commonly known as the spreading marigold or the prostrate calendula. The plant is native to southern Europe, and can also be found in parts of Asia and North Africa.
General Appearance
The spreading marigold is a low-growing, herbaceous plant that typically measures up to 30 cm in height. It has a spreading growth habit, with multiple stems radiating from a central point. The leaves of the plant are lance-shaped, and are typically green or grey-green in color. The plant produces bright yellow or orange flowers that grow up to 6 cm in diameter. The flowers have a pungent aroma and bloom from late spring through to early autumn.
Uses
Calendula diffusa Salisb. has a long history of use in traditional medicine. The plant has anti-inflammatory, antiviral, and antibacterial properties, and has been used to treat a range of skin conditions, including eczema, dermatitis, and wound healing. The petals of the plant can also be used to make teas, tinctures, and extracts, which are believed to have a range of health benefits. Calendula diffusa Salisb. is also commonly used in cosmetics and skincare products due to its soothing and moisturizing properties.
Light Requirements
Calendula diffusa Salisb. typically grows best in full sunlight. In shaded areas, the plant may still grow but will not produce as many flowers as one grown in full sunlight. It is important to note that the plant cannot tolerate extreme heat and may require some shade during the hottest part of the day in very warm climates
Temperature Requirements
Calendula diffusa Salisb. can tolerate a wide range of temperatures, but it is best to keep them within 15°C to 25°C. During the hottest months, it is important to provide the plant with sufficient water to prevent dehydration. It is important to note that the plant cannot tolerate frost and should be protected during freezing temperatures.
Soil Requirements
The plant prefers well-drained soil, rich in organic matter. It can grow in a range of soil pH from 6 to 7.5. Calendula diffusa Salisb. is also tolerant of sandy or loamy soils, as long as they are well-drained, loose and aerated. In order to promote healthy growth, it is important to provide the plant with adequate water and nutrients. The addition of compost or other organic materials can help improve soil quality and fertility.
Cultivation Methods
Calendula diffusa Salisb. can be grown in full sun to partial shade. It requires well-draining soil and prefers a pH ranging from 6.0 to 7.0. The best time to plant is in the spring, after the last frost has passed.
Watering Needs
Calendula diffusa Salisb. requires regular watering, especially during dry periods. However, care should be taken not to overwater as this can lead to root rot. Watering on a weekly basis is usually sufficient, but this may vary depending on soil type and weather conditions.
Fertilization
Fertilizing Calendula diffusa Salisb. once a month during the growing season will promote healthy growth and flowering. A balanced fertilizer is recommended, such as a 10-10-10 or 20-20-20 blend. Care should be taken not to over-fertilize, as this can result in lush foliage but few flowers.
Pruning
Pruning Calendula diffusa Salisb. is not necessary, but deadheading spent flowers will encourage the growth of new blooms. Pinching back the tips of the plant can also promote bushier growth.
Propagation of Calendula diffusa Salisb.
Calendula diffusa Salisb., also known as the spreading marigold, is a plant species that belongs to the Asteraceae family. It is native to South Africa and is commonly grown as an ornamental plant due to its bright yellow flowers that bloom for several months.
Propagation methods
Propagation of Calendula diffusa Salisb. can be done through the following methods:
Seeds
Seeds are the most common method of Calendula diffusa Salisb. propagation. The seeds can be directly sown in the soil during spring or fall. The ideal temperature for germination is between 15 to 18 °C. It takes 7-10 days for the seeds to germinate and 60-80 days for them to flower.
Cuttings
Cuttings can also be used to propagate Calendula diffusa Salisb. Take a cutting from the plant's stem in early summer and dip the cut end in rooting hormone powder. Then place the cutting in a pot with well-draining soil and keep it in a warm and humid location. In a few weeks, the cutting will develop roots and can be transplanted into the garden.
Division
Division is another propagation method for Calendula diffusa Salisb. This method involves dividing the root ball of an established plant into several portions and planting them separately. It is best to do this in the spring when the plant starts to grow actively again. Make sure to water the new plants regularly until they establish themselves in the garden.
Disease Management
Calendula diffusa Salisb. is generally a hardy plant that is resistant to most diseases if provided with suitable growing conditions. However, the plant can be susceptible to various diseases that can cause damage to the foliage and flowers. Some of the common diseases that might affect the plant include:
- Root rot: This disease is caused by overwatering, poor drainage, or infestation by soil-dwelling fungi. The infected plant might show stunted growth, yellowing of leaves, and wilting. To manage root rot, ensure the soil is well-draining, and avoid overwatering.
- Fungal leaf spot: The disease is caused by fungi that thrive in humid and damp conditions. Symptoms include the appearance of brown or black spots on the leaves. To manage fungal leaf spot, remove and dispose of the infected leaves, avoid watering the foliage, and apply fungicides.
- Botrytis blight: This disease is caused by the fungus Botrytis cinerea, which attacks the flowers and leaves of the plant. Symptoms include grayish brown moldy growth on the leaves and flowers. To manage botrytis blight, remove the infected plant parts and avoid overhead irrigation.
Pest Management
Calendula diffusa Salisb. can also be infested by various pests that can cause significant damage to the plant. Some of the common pests that might affect the plant include:
- Aphids: These are tiny insects that feed on the sap of the plant, causing the leaves to wilt and yellow. To manage aphids, spray the plant with insecticidal soap or neem oil.
- Spider mites: These are tiny pests that feed on the plant sap, causing yellowing or bronzing of leaves. To manage spider mites, apply neem oil or insecticidal soap to the foliage.
- Cutworms: These are caterpillars that feed on the plant stems and foliage, causing wilting and stunted growth. To manage cutworms, handpick them from the plant or apply insecticides containing Bacillus thuringiensis.
